JP4841058B2 - Adhesive sheet and adhesive - Google Patents

Description

【０１７３】
表１から明らかなように、実施例１〜６では、帯電防止層表面の表面抵抗率は、１０⁶〜１０⁸Ωと適正な範囲の値で、粘着剤層表面の表面抵抗率に関わらず、剥離帯電圧は、いずれも検出限界以下であり、優れた帯電防止効果が認められた。また、イオン量、シリコーン化合物量は、検出下限値以下であった。
【０１７４】
これに対し、比較例１では、帯電防止層表面の表面抵抗率は、１０⁸Ωと適正な範囲の値で、剥離帯電圧は、検出下限値以下であったが、イオン量は、１．４ｍｇ／ｍ²、シリコーン化合物量は、５０００μｇ／ｍ²であった。
【０１７５】
また、比較例２では、イオン量およびシリコーン化合物量は、検出下限値以下であったが、剥離帯電圧は、５．０ｋＶであった。また、離型シートを粘着シートから剥離する際、粘着シートがピンセットの先に巻き付き、操作性も劣っていた。
【０１７６】
【発明の効果】
以上述べたように、本発明によれば、剥離帯電の発生を防止し、かつ実質的にイオンを含有していない粘着シートおよび貼着体を得ることができる。
【０１７７】
よって、本発明の粘着シートや貼着体を用いれば、粘着シートを剥離する際の操作性の低下を防止することができるとともに、静電気やイオンの存在を原因とするハードディスクドライブ装置等の性能の劣化、破損等の発生を防止することができる。
【０１７８】
また、粘着シート、貼着体中にシリコーン化合物を実質的に含まないようにすることにより、ハードディスクドライブ装置は、トラブルがより発生しにくいものとなり、装置としての信頼性がさらに向上する。
【０１７９】
特に、離型剤としてオレフィン系熱可塑性エラストマーおよびポリエチレン樹脂を用いた場合、離型性がより優れたものとなり、離型シートを簡便、確実に剥離することができる。
【図面の簡単な説明】
【図１】本発明の貼着体の第１実施形態を示す断面図である。
【図２】本発明の貼着体の第２実施形態を示す断面図である。
【符号の説明】
１ａ、１ｂ 貼着体
２ａ、２ｂ 粘着シート
２１ 基材
２２ 帯電防止層
２２１、２２２ 帯電防止層
２３ 粘着剤層
２３１、２３２ 粘着剤層
３ 離型シート
３１ 離型シート基材
３２ 離型剤層[0001]
[Technical field to which the invention belongs]
The present invention relates to a pressure-sensitive adhesive sheet and a sticking body.
[0002]
[Prior art]
Hard disk drive devices are widely used as peripheral devices for computers.
[0003]
At the time of manufacturing or assembling this hard disk drive device or its parts, for the purpose of temporarily fixing the parts, displaying the name and number of the parts, and closing holes provided in the main body and lid for inspection etc. An adhesive sheet is used.
[0004]
Such an adhesive sheet is usually composed of a base material and an adhesive layer, and is attached to a release sheet before being attached to a hard disk drive device or the like.
[0005]
At the time of sticking, the release sheet is peeled off from the pressure-sensitive adhesive sheet. At this time, peeling charging may occur between the release sheet and the pressure-sensitive adhesive sheet. When peeling electrification occurs, there arises a disadvantage that the release sheet is wound around tweezers used for peeling. In some cases, the hard disk drive device or its components may be adversely affected such as destruction.
[0006]
For the purpose of preventing such peeling electrification, a layer provided with an antistatic layer containing an antistatic agent has been proposed (for example, JP-A-9-190990).
[0007]
However, in this semiconductor wafer fixing sheet, an ionic material such as an anionic or cationic surfactant is used as an antistatic agent. Therefore, when such an adhesive sheet containing an antistatic agent is used for a hard disk drive device or the like, ions present in the antistatic layer adhere to the hard disk drive device or its components via the adhesive layer or the like. As a result, there is a possibility of causing problems such as contact failure and performance deterioration in the hard disk drive device or its components.
[0008]
Moreover, the release agent layer is provided in the surface (contact surface with an adhesive layer) of such a release sheet for the purpose of a mold release improvement. Conventionally, silicone resin has been used as a constituent material of the release agent layer.
[0009]
However, it is known that when such a release sheet is attached to an adhesive sheet, silicone compounds such as low molecular weight silicone resin, siloxane, and silicone oil in the release sheet migrate to the adhesive layer of the adhesive sheet. Yes. In addition, the release sheet is wound into a roll after manufacture, and at this time, the back surface of the release sheet and the release agent layer are in contact, and the silicone compound in the silicone resin moves to the back surface of the release sheet. To do. It is also known that the silicone compound transferred to the back surface of the release sheet is transferred again to the surface of the pressure-sensitive adhesive sheet when the adhesive body is wound into a roll at the time of manufacturing the adhesive body. For this reason, when the adhesive sheet attached to such a release sheet is attached to the hard disk drive device, the silicone compound that has migrated to the surface of the adhesive layer or the adhesive sheet is then gradually vaporized and magnetically It is known that a fine silicone compound layer is formed by depositing on the head or the disk surface.
[0010]
[Problems to be solved by the invention]
An object of the present invention is to provide a pressure-sensitive adhesive sheet and a sticking body that do not adversely affect the hard disk drive device or its components.
[0011]
[Means for Solving the Problems]
  Such purposes are as follows (1) to (7This is achieved by the present invention.
[0012]
  (1) An adhesive sheet used in a manufacturing process or an assembling process of a hard disk drive device or its parts,
  A base material, a pressure-sensitive adhesive layer composed of a pressure-sensitive adhesive, and a nonionic antistatic layer interposed therebetween,
  The antistatic layer is a π electron conjugated conductive polymer as an antistatic agent.PolyanilineA pressure-sensitive adhesive sheet comprising:
[0015]
  (2The surface resistivity of the antistatic layer is 1 × 10^Four~ 1x10¹²Ω above(1)The pressure-sensitive adhesive sheet described in 1.
[0016]
  (3The pressure-sensitive adhesive sheet is substantially free from a silicone compound (1)Or (2)The pressure-sensitive adhesive sheet described in 1.
[0017]
  (4) The above (1) to (1), wherein the antistatic layer and the pressure-sensitive adhesive layer are provided on both sides of the substrate, respectively.3) The pressure-sensitive adhesive sheet according to any one of the above.
[0018]
  (5) Above (1) to (4), A release sheet overlaid on the pressure-sensitive adhesive layer of the pressure-sensitive adhesive sheet.
[0019]
  (6The release sheet is substantially free of a silicone compound.5).
[0020]
  (7The above release sheet has a release agent layer containing an olefinic thermoplastic elastomer and a polyethylene resin.5) Or (6).
[0021]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the adhesive sheet and the sticking body of the present invention will be described in detail based on preferred embodiments.
[0022]
FIG. 1 is a schematic cross-sectional view showing a first embodiment of the sticking body of the present invention.
[0023]
As shown in the figure, the sticking body 1a of the present invention has a pressure-sensitive adhesive sheet 2a having a base material 21, a pressure-sensitive adhesive layer 23, and an antistatic layer 22 interposed therebetween, and the pressure-sensitive adhesive sheet 2a. The release sheet 3 is adhered to the pressure-sensitive adhesive layer 23. The release sheet 3 includes a release sheet substrate 31 and a release agent layer 32, and the release agent layer 32 is bonded to the pressure-sensitive adhesive layer 23.
[0024]
The sticking body 1a of the present invention is used in a manufacturing process or an assembling process of a hard disk drive device or a component thereof (hereinafter simply referred to as “hard disk drive device”).
[0025]
In the sticking body 1a, the pressure-sensitive adhesive sheet 2a can be peeled from the release sheet 3. After peeling, for example, the pressure-sensitive adhesive sheet 2a is stuck to a hard disk drive device. Hereinafter, an example in which the hard disk drive device is used as an adherend will be described.
[0026]
First, the adhesive sheet 2a will be described.
The pressure-sensitive adhesive sheet 2 a has a configuration in which an antistatic layer 22 and a pressure-sensitive adhesive layer 23 are formed in this order on a base material 21.
[0027]
The base material 21 has a function of supporting the antistatic layer 22 and the pressure-sensitive adhesive layer 23. For example, a polyester film such as polyethylene terephthalate or polybutylene terephthalate, a plastic film such as polypropylene or polystyrene, or a metal such as aluminum or stainless steel. It is composed of a simple substance such as foil, dust-free paper, synthetic paper, or a composite material.
[0028]
Among these, it is particularly preferable that the substrate 21 is made of a polyester film such as polyethylene terephthalate or polybutylene terephthalate, a plastic film such as polypropylene, or dust-free paper. Since the substrate 21 is made of a plastic film or dust-free paper, dust and the like are hardly generated during processing and use, and the hard disk drive device is not adversely affected. Further, cutting or punching during processing becomes easy. Moreover, when using a plastic film for the base material 21, it is more preferable that this plastic film is comprised with the polyethylene terephthalate film. Polyethylene terephthalate film has the advantages that it generates less dust and generates less gas during heating.
[0029]
Although the thickness of the base material 21 is not specifically limited, It is preferable that it is 10-200 micrometers, and it is more preferable that it is 25-100 micrometers.
[0030]
The substrate 21 may be printed or printed on the surface thereof (the surface opposite to the surface on which the antistatic layer 22 and the pressure-sensitive adhesive layer 23 are laminated). Moreover, the surface of the base material 21 may be subjected to surface treatment for the purpose of improving the adhesion of printing or printing. Moreover, the adhesive sheet 2a may function as a label.
[0031]
The antistatic layer 22 has an effect of preventing the occurrence of peeling charge (antistatic effect), and in particular, has an effect of effectively preventing the occurrence of peeling charge when the pressure-sensitive adhesive sheet 2a is peeled from the release sheet 3. . In addition, even when a voltage is generated near the adhesion site of the adhesive sheet 2a, it can be safely grounded.
[0032]
The antistatic layer 22 is substantially free of ions (nonionic).
Since the antistatic layer 22 is nonionic, the generation of ions from the antistatic layer 22 can be prevented. Therefore, migration of ions to the hard disk drive device and its components can be prevented, and as a result, problems such as poor contact and performance degradation in the hard disk drive device can be prevented.
[0033]
As described above, preferable examples of the nonionic antistatic layer 22 include the following [1] and [2].
[0034]
[1] An antistatic agent composition comprising at least one antistatic agent of carbon black, a metal-based conductive filler, a metal oxide-based conductive filler, and a π-electron conjugated conductive polymer
Examples of the metallic conductive filler include metal powders such as Cu, Al, Ni, Sn, and Zn.
[0035]
When carbon black or a metallic conductive filler is used as the antistatic agent, for example, those conductive fillers dispersed in a binder are used. Although the addition amount of the conductive filler in the antistatic agent composition is not particularly limited, it is preferably 1 to 90 wt%, and more preferably 3 to 80 wt%.
[0036]
If the amount of carbon black and metal-based conductive filler added is less than 1 wt%, a sufficient antistatic effect may not be obtained. On the other hand, when the addition amount of the conductive filler exceeds 90 wt%, the strength decreases, and when the pressure-sensitive adhesive sheet 2 a is peeled from the release sheet 3, there is a possibility that the antistatic layer 22 is cohesive or interfacial broken.
[0037]
In addition, as the binder, for example, high molecular polymers such as acrylic, urethane, polyester, epoxy, polyvinyl chloride, melanin, and polyimide are used, and if necessary, a crosslinking agent or the like. Additives are blended.
[0038]
Examples of the metal oxide conductive filler include zinc oxide, titanium oxide, tin oxide, indium oxide, and antimony oxide.
[0039]
When a metal oxide conductive filler is used as the antistatic agent, the metal oxide conductive filler is, for example, in a state of being dispersed in a binder. The addition amount of the metal oxide conductive filler in the antistatic agent composition is not particularly limited, but is preferably 10 to 90 wt%, and more preferably 20 to 80 wt%.
[0040]
If the addition amount of the metal oxide conductive filler is less than 10 wt%, a sufficient antistatic effect may not be obtained. On the other hand, when the addition amount of the metal oxide conductive filler exceeds 90 wt%, the strength decreases, and when the pressure-sensitive adhesive sheet 2 a is peeled from the release sheet 3, cohesive failure or interface failure of the antistatic layer 22 occurs. there is a possibility.
[0041]
Moreover, as said binder, the thing similar to what is used for carbon black and a metallic conductive filler is used, and additives, such as a crosslinking agent, are mix | blended as needed.
[0042]
The above-mentioned antistatic agent is, for example, coated with the above-described carbon black, metal-based conductive filler, metal oxide-based conductive filler, etc. on the surface of resin powder or glass powder such as polystyrene or polymethacrylate. It may be processed by sputtering or the like.
[0043]
The π-electron conjugated conductive polymer is a polymer obtained by polymerizing a monomer having a conjugated double bond in a molecular structure by oxidation.
[0044]
Examples of the monomer constituting the π-electron conjugated conductive polymer include aniline, thiophene, pyrrole, and derivatives thereof.
[0045]
The average molecular weight of the π-electron conjugated conductive polymer is not particularly limited, but is preferably about several hundred to several tens of thousands.
[0046]
The antistatic agent composition may contain a π-electron conjugated conductive polymer and a metal oxide conductive filler. In this case, the binder described above may or may not be included.
[0047]
In particular, as a method for forming the antistatic layer 22 containing a π-electron conjugated conductive polymer, for example, a method of applying an antistatic agent composition containing a π-electron conjugated conductive polymer on the pressure-sensitive adhesive sheet substrate 21, Examples thereof include a method in which a monomer constituting the π-electron conjugated conductive polymer is brought into contact with the surface of the pressure-sensitive adhesive sheet substrate 21 and polymerized in the presence of an oxidizing agent. When using a method in which a monomer constituting a π-electron conjugated conductive polymer is brought into contact with the surface of the pressure-sensitive adhesive sheet base material 21 and polymerized in the presence of an oxidizing agent, for example, the base film is placed in a solution containing an oxidizing agent. Examples include a method in which a monomer is polymerized by dipping (immersion polymerization method), and a conductive polymer layer is obtained by directly depositing a conductive polymer on the surface of the base film. According to this method, the monomer concentration can be arbitrarily changed, and the thickness and conductivity of the conductive polymer layer can be easily controlled.
[0048]
Examples of the oxidizing agent include peroxodisulfates such as ammonium peroxodisulfate and potassium peroxodisulfate, ferric salts such as ferric chloride, ferric sulfate, and ferric nitrate, potassium permanganate, and permanganate. Examples thereof include permanganates such as sodium phosphate, and dichromates such as sodium dichromate and potassium dichromate.
[0049]
Further, the antistatic agent composition may contain various additives such as a plasticizer, a tackifier, and a stabilizer as necessary.
[0050]
[2] Consists of metal or metal oxide thin films
Examples of the metal thin film include thin films such as Al, Ti, Au, Ag, Pd, Ni, Pt, and alloys containing these metals. For example, the metal thin film may be a laminate of a plurality of layers having different compositions.
[0051]
Examples of the metal oxide thin film include thin films of manganese oxide, titanium oxide, and the like. The metal oxide thin film may contain a dopant in the metal oxide, such as ITO or ATO, or may contain a plurality of metal elements.
[0052]
Examples of the method for forming a metal or metal oxide thin film include chemical vapor deposition (CVD) such as thermal CVD, plasma CVD, and laser CVD, and physical vapor deposition (PVD) such as vacuum deposition, sputtering, and ion plating. Can be mentioned.
[0053]
The antistatic layer 22 may be a laminate of a plurality of layers having different compositions. For example, the antistatic layer 22 is formed by laminating a layer containing at least one antistatic agent of the above-described metal oxide conductive filler and π electron conjugated conductive polymer, and a metal or metal oxide thin film. It may be a thing.
[0054]
The surface resistivity of the antistatic layer 22 obtained in this way is 10^Four-10¹²Preferably it is Ω.⁶-10⁹More preferably, it is Ω.
[0055]
The surface resistivity of the surface of the antistatic layer 22 is 10^FourIf it is less than Ω, there is a possibility that components such as an IC and a magnetic head are damaged when a voltage is generated for some reason. On the other hand, the surface resistivity of the surface of the antistatic layer 22 is 10¹²If it exceeds Ω, there is a possibility that sufficient antistatic effect cannot be obtained.
[0056]
The thickness of the antistatic layer 22 may be appropriately determined so as to have the above surface resistivity. However, in the case of carbon black, metal-based conductive filler, metal oxide-based conductive filler, and π-electron conjugated conductive polymer 0.01 to 20 μm is preferable, and 0.1 to 1 μm is more preferable. The metal or metal oxide thin film is preferably 0.005 to 1 μm. If the thickness of the antistatic layer 22 is less than the lower limit, a sufficient antistatic effect may not be obtained. On the other hand, when the thickness of the antistatic layer 22 exceeds the upper limit value, the rigidity of the pressure-sensitive adhesive sheet 2a may be lowered or the transparency may be lowered.
[0057]
The pressure-sensitive adhesive layer 23 is composed of a pressure-sensitive adhesive composition mainly containing a pressure-sensitive adhesive.
Examples of the pressure sensitive adhesive include acrylic pressure sensitive adhesive, polyester pressure sensitive adhesive, and urethane pressure sensitive adhesive. Among them, the pressure-sensitive adhesive is particularly preferably an acrylic pressure-sensitive adhesive.
[0058]
By using an acrylic pressure-sensitive adhesive as the pressure-sensitive adhesive, a pressure-sensitive adhesive sheet 2a from a mold release sheet 3 (particularly, a mold release sheet 3 in which the mold release agent layer 32 is composed of an olefinic thermoplastic elastomer and a polyethylene resin) is used. The releasability of is extremely excellent.
[0059]
For example, when the pressure-sensitive adhesive is an acrylic pressure-sensitive adhesive, the main monomer component that provides tackiness, the comonomer component that provides adhesiveness and cohesion, and the functional group-containing monomer component for improving the cross-linking point and adhesion are mainly used. It can be composed of a polymer or a copolymer.
[0060]
As the main monomer component, for example, acrylic acid alkyl esters such as ethyl acrylate, butyl acrylate, amyl acrylate, 2-ethylhexyl acrylate, octyl acrylate, cyclohexyl acrylate, benzyl acrylate, methoxyethyl acrylate, Examples include methacrylic acid alkyl esters such as butyl methacrylate, 2-ethylhexyl methacrylate, cyclohexyl methacrylate, and benzyl methacrylate.
[0061]
Examples of the comonomer component include methyl acrylate, methyl methacrylate, ethyl methacrylate, vinyl acetate, styrene, acrylonitrile, and the like.
[0062]
Examples of the functional group-containing monomer component include carboxyl group-containing monomers such as acrylic acid, methacrylic acid, maleic acid, and itaconic acid, 2-hydroxyethyl (meth) acrylate, and 2-hydroxypropyl (meth) acrylate. And hydroxyl group-containing monomers such as N-methylolacrylamide, acrylamide, methacrylamide, glycidyl methacrylate and the like.
[0063]
By including these components, the adhesive force and cohesive force of the pressure-sensitive adhesive composition are improved. In addition, since such an acrylic resin usually does not have an unsaturated bond in the molecule, stability to light and oxygen can be improved. Furthermore, a pressure-sensitive adhesive composition having quality and characteristics according to the application can be obtained by appropriately selecting the type and molecular weight of the monomer.
[0064]
As such a pressure-sensitive adhesive composition, any of a crosslinked type that undergoes crosslinking treatment and a non-crosslinked type that does not undergo crosslinking treatment may be used, but a crosslinked type is more preferred. When a cross-linked type is used, a pressure-sensitive adhesive layer with better cohesion can be formed.
[0065]
Examples of the crosslinking agent used in the crosslinking adhesive composition include an epoxy compound, an isocyanate compound, a metal chelate compound, a metal alkoxide, a metal salt, an amine compound, a hydrazine compound, and an aldehyde compound.
[0066]
Moreover, in the adhesive composition used for this invention, various additives, such as a plasticizer, a tackifier, and a stabilizer, may be contained as needed.
[0067]
Although the thickness of the adhesive layer 23 is not specifically limited, It is preferable that it is 1-70 micrometers, and it is more preferable that it is 10-40 micrometers.
[0068]
It is preferable that the entire pressure-sensitive adhesive sheet 2a is substantially free of ions.
[0069]
For example, NO contained in the entire adhesive sheet 2a_x ^-, Cl^-, PO_Four ^3-, F^-, SO_Four ^2-, K⁺, Na⁺, Ca²⁺The total amount (hereinafter also simply referred to as “ion amount”) of 1 mg / m²Or less, preferably 0.1 mg / m²The following is more preferable. If the pressure-sensitive adhesive sheet 2a contains a large amount of such ions, after the pressure-sensitive adhesive sheet 2a is attached to the hard disk drive device, the ions adhere to the hard disk drive device through an operator's gloves or the like and have an adverse effect. There is a fear. On the other hand, if the amount of ions is less than or equal to the above-described numerical value, the amount of ions generated from the pressure-sensitive adhesive sheet 2a becomes extremely small, and the hard disk drive device is less susceptible to adverse effects.
[0070]
Such an ion amount can be measured, for example, as follows. First, the sticking body 1 a is cut into a predetermined shape and area, and then the pressure-sensitive adhesive sheet 2 a is peeled from the release sheet 3. Next, extraction operation is performed on the pressure-sensitive adhesive sheet 2a using 80 ° C. pure water. Next, the obtained extract is analyzed using an ion chromatograph analyzer. Then, the amount of ions per unit area is obtained from the obtained measurement result.
[0071]
The period from when the sticking body 1a is manufactured to when it is stuck to the hard disk drive device is usually about 30 days. Therefore, the sticking body 1a has an ion amount of 1 mg / m in the pressure-sensitive adhesive sheet 2a after at least 30 days have passed since the manufacture.²Or less, preferably 0.1 mg / m²The following is more preferable.
[0072]
It can be said that the pressure-sensitive adhesive sheet 2a is extremely difficult to adversely affect the hard disk drive device when the amount of ions is not more than the above-described value even after 30 days have passed since the sticking body 1a was manufactured.
[0073]
Moreover, it is preferable that the adhesive sheet 2a does not contain a silicone compound substantially.
[0074]
For example, the content of the silicone compound in the adhesive sheet 2a is 500 μg / m.²Or less, preferably 100 μg / m²It is preferable that:
[0075]
Examples of the silicone compound include low molecular weight silicone resin, silicone oil, siloxane and the like.
[0076]
The content of the silicone compound in the adhesive sheet 2a is 500 μg / m.²When the adhesive sheet 2a is attached to the hard disk drive device, the amount of silicone compound released from the adhesive sheet 2a is extremely small. Therefore, if the adhesive sheet 2a is used, it is possible to prevent the phenomenon that the silicone compound is released from the adhesive sheet 2a and the silicone compound is deposited on the magnetic head or the disk surface. Therefore, if the adhesive sheet 2a of the present invention is used in the hard disk drive device, the hard disk drive device is less likely to cause trouble, and the reliability as the device is further improved.
[0077]
Such an effect is obtained by reducing the content of the silicone compound in the pressure-sensitive adhesive layer 23 and the substrate 21 to 100 μg / m.²The following can be obtained more remarkably.
[0078]
In addition, content of a silicone compound can be measured as follows, for example. First, the sticking body 1 a is cut into a predetermined shape and area, and then the pressure-sensitive adhesive sheet 2 a is peeled from the release sheet 3. Next, extraction operation is performed with respect to the adhesive sheet 2a using a solvent. Next, the obtained extract is dried. Next, a tablet is prepared from the obtained dried product and a predetermined amount of potassium bromide, and the content of the silicone compound in the tablet is measured by a beam condenser type FT-IR. Then, the content of the silicone compound per unit area is obtained from the obtained measurement result.
[0079]
In this case, from the same viewpoint as described above, the measurement of the content of the silicone compound is preferably performed after at least 30 days have passed since the sticking body 1a was manufactured.
[0080]
A release sheet 3 is usually attached to such an adhesive sheet 2a until just before use. The above-described characteristics of the pressure-sensitive adhesive sheet 2a greatly depend on the composition and properties of the release sheet 3, particularly the release agent layer 32. In order for the adhesive sheet 2a to obtain the above-described characteristics, the release sheet 3 is preferably as described below.
[0081]
The release sheet 3 has a configuration in which a release agent layer 32 is formed on a release sheet substrate 31.
[0082]
The release sheet 3 is preferably substantially free of ions and silicone compounds, but may be included as long as ions and silicone compounds are not transferred to the surface of the pressure-sensitive adhesive layer 23 or the surface of the base material 21. . Thereby, the transfer of the ion and the silicone compound from the release sheet 3 to the pressure-sensitive adhesive sheet 2a (particularly, the pressure-sensitive adhesive layer 23) can be prevented.
[0083]
The amount of ions in the release sheet 3 is, for example, 1 mg / m²Or less, preferably 0.1 mg / m²The following is more preferable.
[0084]
The content of the silicone compound in the release sheet 3 is, for example, 500 μg / m.²Or less, preferably 100 μg / m²It is preferable that:
[0085]
By making the amount of ions and the amount of silicone compound in the release sheet 3 less than the lower limit, the amount of ions in the pressure-sensitive adhesive sheet 2a is relatively easily reduced to 1 mg / m.²The following (further 0.1 mg / m²In addition, the content of the silicone compound is 500 μg / m²The following (and further 100 μg / m²The following can be suppressed. As a result, the hard disk drive device or the like to which the adhesive sheet 2a is attached is not easily affected.
[0086]
The release sheet substrate 31 has a function of supporting the release agent layer 32. For example, a polyester film such as a polyethylene terephthalate film or a polybutylene terephthalate film, a polyolefin film such as a polypropylene film or a polymethylpentene film, It is composed of a plastic film such as a polycarbonate film, a metal foil such as aluminum or stainless steel, glassine paper, fine paper, coated paper, dust-free paper, impregnated paper, synthetic paper or the like.
[0087]
Among them, in particular, the release sheet substrate 31 is a polyester film such as a polyethylene terephthalate film or a polybutylene terephthalate film, a plastic film such as a polypropylene film, or a so-called dust-free paper with little dust generation (for example, Japanese Patent Publication No. 6-11959). It is preferable that it is comprised. When the release sheet base 31 is made of a plastic film or dust-free paper, dust and the like are hardly generated during processing and use, and the hard disk drive device is not adversely affected. Further, when the release sheet base 31 is made of a plastic film or dust-free paper, cutting or punching during processing becomes easy. Moreover, when using a plastic film for the release sheet base material 31, it is more preferable that the plastic film is a polyethylene terephthalate film. The polyethylene terephthalate film has the advantages that it generates less dust and generates less gas during heating.
[0088]
Although the thickness of the release sheet base material 31 is not specifically limited, It is preferable that it is 10-200 micrometers, and it is more preferable that it is 50-150 micrometers.
[0089]
The release agent layer 32 provided on the release sheet substrate 31 is bonded to the pressure-sensitive adhesive sheet 2a and has a release action.
[0090]
The release agent layer 32 is composed of a release agent.
Examples of the release agent used for the release agent layer 32 include polyolefins such as polyethylene, thermoplastic elastomers such as olefinic thermoplastic elastomers, fluororesins such as tetrafluoroethylene, and mixtures thereof.
[0091]
Among these, as a preferable mold release agent used for the mold release agent layer 32, one containing polyolefin and an olefin-based thermoplastic elastomer can be cited. When the release agent layer 32 is composed of such a release agent, a sufficient release property can be obtained without containing in the release agent layer 32 a substance that tends to adversely affect the hard disk drive device such as a silicone compound. Is obtained. Therefore, when the release agent layer 32 is composed of polyethylene and an olefin-based thermoplastic elastomer, an environment in which a silicone compound or the like moves from the release agent layer 32 to the pressure-sensitive adhesive layer 23 is formed in the adhesive body 1a. Can be suitably prevented.
[0092]
When the release agent layer 32 contains the olefin-based thermoplastic elastomer and the polyethylene resin, in addition to the effects described above, excellent release properties can be obtained. Therefore, when the release agent layer 32 contains an olefin-based thermoplastic elastomer and a polyethylene resin, the amount of ions in the pressure-sensitive adhesive sheet 2a can be set to 1 mg / m relatively easily.²The following (further 0.1 mg / m²In addition, the content of the silicone compound is 500 μg / m²The following (and further 100 μg / m²The pressure-sensitive adhesive sheet 2a can be easily and reliably peeled from the release sheet 3 as well as the following.
[0093]
When the release agent layer 32 contains an olefinic thermoplastic elastomer and a polyethylene resin, the olefinic thermoplastic elastomer and the polyethylene resin preferably satisfy the following conditions.
[0094]
Examples of the olefin-based thermoplastic elastomer include those having an ethylene propylene copolymer, an ethylene octene copolymer or the like as a main component. Among these, an ethylene propylene copolymer is particularly preferable.
[0095]
By using an ethylene propylene copolymer as a main component, a release sheet having particularly excellent release properties can be obtained.
[0096]
The olefin-based thermoplastic elastomer can include polypropylene and polyethylene.
[0097]
Examples of commercially available olefin-based thermoplastic elastomers in the present invention include the Tuffmer series (manufactured by Mitsui Chemicals).
[0098]
The density of the olefinic thermoplastic elastomer is 0.80-0.90 g / cm.^ThreePreferably, 0.86-0.88 g / cm^ThreeIt is more preferable that
[0099]
If the density of the olefinic thermoplastic elastomer is less than the lower limit, sufficient heat resistance may not be obtained.
[0100]
On the other hand, if the density of the olefin-based thermoplastic elastomer exceeds the upper limit value, sufficient releasability may not be obtained.
[0101]
The density of the polyethylene resin is not particularly limited, but is 0.890 to 0.925 g / cm.^ThreePreferably, 0.900 to 0.922 g / cm^ThreeIt is more preferable that
[0102]
If the density of the polyethylene resin is less than the lower limit value or exceeds the upper limit value, sufficient releasability may not be obtained.
[0103]
Such a polyethylene resin is preferably synthesized using a transition metal catalyst such as a Ziegler-Natta catalyst or a metallocene catalyst.
[0104]
Especially, what was synthesize | combined using the metallocene catalyst has the advantage that it is excellent in mold release property and heat resistance.
[0105]
Examples of the polyethylene resin include those produced using a Ziegler-Natta catalyst, such as J-REX series (manufactured by Nippon Polyolefin Co., Ltd.), Excellen series (manufactured by Sumitomo Chemical Co., Ltd.), HIα series (manufactured by Sumitomo Chemical Co., Ltd.), and the like. Kernel series (made by Nippon Polychem), Sumikasen E series (made by Sumitomo Chemical), Excellen E series (made by Sumitomo Chemical), Excellen EX series (made by Sumitomo Chemical) ) And the like.
[0106]
Note that the release agent layer 32 may include, for example, two or more types of polyethylene resins having different compositions, densities, and the like.
[0107]
The weight ratio (blending ratio) between the olefinic thermoplastic elastomer and the polyethylene resin is not particularly limited, but is preferably 25:75 to 75:25, and more preferably 40:60 to 60:40.
[0108]
If the content of the olefinic thermoplastic elastomer is too small, sufficient releasability may not be obtained depending on the type of the olefinic thermoplastic elastomer or polyethylene resin.
[0109]
On the other hand, if the content of the olefinic thermoplastic elastomer is too large, sufficient heat resistance may not be obtained depending on the type of the olefinic thermoplastic elastomer or polyethylene resin.
[0110]
The thickness of the release agent layer 32 is not particularly limited, but is preferably 5 to 50 μm, and more preferably 15 to 30 μm.
[0111]
When the thickness of the release agent layer is within this range, an effect that the releasability is good is obtained.
[0112]
The release sheet may have a configuration in which a release agent layer is formed on a release sheet substrate via an adhesion enhancing layer as an intermediate layer.
[0113]
As a result, the adhesion between the release agent layer and the release sheet substrate is improved, and when the release sheet is peeled from the pressure-sensitive adhesive sheet, at the boundary surface between the release agent layer and the release sheet substrate. It is possible to more suitably prevent peeling or part of the release agent layer from remaining on the pressure-sensitive adhesive layer after peeling.
[0114]
Examples of the material constituting the adhesion enhancing layer include polyethylene, modified polyethylene, and other adhesive polyolefins.
[0115]
For the release sheet, a release sheet base material is prepared, and an adhesion enhancing layer is formed on the release sheet base material by coating the constituent material of the adhesion enhancing layer. It can be prepared by applying a release agent or the like to form a release agent layer.
[0116]
The thickness of the adhesion enhancing layer is not particularly limited, but is preferably 0.1 to 50 μm, and more preferably 3 to 20 μm.
[0117]
Examples of the method for coating the constituent material of the adhesion enhancing layer on the release sheet substrate include extrusion lamination.
[0118]
In the present embodiment, the intermediate layer is an adhesion enhancing layer that enhances the adhesive strength between the release agent layer and the release sheet substrate, but the intermediate layer may be used for other purposes. Good. For example, the intermediate layer may be a barrier layer that prevents migration of components between the release agent layer and the release sheet substrate. Moreover, the release sheet may have two or more intermediate layers.
[0119]
In the sticking body 1a composed of such a release sheet 3 and the pressure-sensitive adhesive sheet 2a, the peeling voltage when peeling the release sheet 3 from the pressure-sensitive adhesive sheet 2a is preferably 0.5 kV or less. More preferably, it is 0.1 kV or less.
[0120]
If the peeling voltage exceeds 0.5 kV, a sufficient antistatic effect may not be obtained.
[0121]
Next, the manufacturing method of the adhesive sheet of this invention and an adhesive body is demonstrated.
The adhesive sheet 2a is manufactured by the following methods, for example.
[0122]
First, the antistatic layer 22 is formed on the base material 21 by the method described above. Furthermore, it is manufactured by providing an adhesive layer 23 on the antistatic layer 22.
[0123]
As a method for forming the pressure-sensitive adhesive layer, for example, a method in which the pressure-sensitive adhesive composition is directly applied to the antistatic layer 22 provided on the substrate 21 with a coater such as a gravure, bar, knife, kiss roll, letterpress, A method of printing with a printing machine such as a lithographic plate, a flexo, an offset, a screen, an intaglio, or a transfer method in which the antistatic layer 22 is formed on a process paper with a coater such as a knife and then adhered to the substrate 21 before the tack disappears. There is. In order to improve the adhesion between the antistatic layer 22 and the pressure-sensitive adhesive layer 23, the antistatic layer 22 may be subjected to treatment such as corona discharge and anchor coating.
[0124]
Examples of the coating liquid form of the pressure-sensitive adhesive composition in this case include a solvent type, an emulsion type, and a hot melt type.
[0125]
In addition, the release sheet 3 is prepared by, for example, preparing a release sheet base 31 and coating the release agent on the release sheet base 31 to form the release agent layer 32. Can be created.
[0126]
Examples of the method for coating the release agent on the release sheet substrate 31 include extrusion lamination.
[0127]
The sticking body 1a can be manufactured, for example, by sticking the pressure-sensitive adhesive sheet 2a and the release sheet 3 thus obtained so that the pressure-sensitive adhesive layer 23 is in contact with the release agent layer 32. .
[0128]
In addition, the adhesive layer 23 is formed on the release agent layer 32 of the release sheet 3, and then the base material 21 on which the antistatic layer 22 is formed by the above-described method is prepared. You may manufacture the sticking body 1a by bonding so that the adhesive layer 23 may contact | connect.
[0129]
In addition, although the case where the hard disk drive device was used as the adherend was described above, the adhesive sheet 2a and the adhesive body 1a of the present invention can be used in the manufacturing process or assembly process of the hard disk drive device. Well, the kind of adherend is not limited.
[0130]
That is, the pressure-sensitive adhesive sheet of the present invention may be used without directly sticking to the hard disk drive device.
[0131]
The pressure-sensitive adhesive sheet of the present invention can also be used as, for example, a dust removal tape or a dust removal roll formed into a roll. For example, in a hard disk drive device manufacturing factory (for example, in a clean room, etc.), it is possible to more effectively prevent contamination of the hard disk drive device to be manufactured by using the adhesive sheet of the present invention as a dust removal tape or the like. Thus, further enhancement of the performance of the hard disk drive device can be achieved.
[0132]
In addition, since the antistatic layer is provided in the present invention, it is possible to more effectively prevent the generation of static electricity when used as a dust removal tape or the like.
[0133]
FIG. 2: is a schematic sectional drawing which shows 2nd Embodiment of the sticking body of this invention.
Hereinafter, the sticking body of the second embodiment will be described with a focus on differences from the first embodiment described above, and description of similar matters will be omitted.
[0134]
In the present embodiment, the pressure-sensitive adhesive sheet 2 b has antistatic layers 221 and 222 formed on both surfaces of the base material 21, and the pressure-sensitive adhesive layers 231 and 232 are respectively formed on the antistatic layers 221 and 222. It has a formed configuration. And the sticking body 1b becomes a structure by which the release sheet 3 was stuck on both surfaces of the adhesive sheet 2b.
[0135]
Thereby, it becomes possible to join different adherends via the adhesive sheet 2b.
[0136]
The antistatic layers 221 and 222 may have substantially the same thickness, composition, etc., or may be different.
[0137]
The pressure-sensitive adhesive layers 231 and 232 may have substantially the same thickness, composition, or the like, or may be different.
[0138]
Moreover, the release sheets 3 adhered to both surfaces of the pressure-sensitive adhesive sheet 2b may have substantially the same thickness, composition, or the like.
[0139]
Moreover, the release sheet 3 adhered to both surfaces of the pressure-sensitive adhesive sheet 2b may have at least one of the structures described above.
[0140]
As mentioned above, although the adhesive sheet and the sticking body of this invention were demonstrated about embodiment of illustration, this invention is not limited to this.
[0141]
【Example】
Next, specific examples of the bonded body of the present invention will be described.
[0142]
1. Fabrication of sticking body
Example 1
By extrusion lamination, an adhesion enhancing layer was formed on one side of the release sheet substrate, and a release agent layer was further formed on the surface of the adhesion enhancing layer to produce a release sheet.
[0143]
An antistatic layer was formed on one side of the substrate by a knife coat method. Furthermore, a pressure-sensitive adhesive layer was formed on the surface of the antistatic layer by a knife coating method to produce a pressure-sensitive adhesive sheet (pressure-sensitive adhesive sheet intended to close the lid hole of the hard disk drive device).
[0144]
A release sheet was bonded to this to produce an adhesive body.
The configuration of each layer is as follows.
[0145]
[1] Base material
Constituent material: Polyethylene terephthalate
Thickness: 38 μm
[0146]
[2] Antistatic layer
Constituent material: Tin oxide conductive filler (Ishihara Sangyo Co., Ltd .: trade name “SN-100P”) 100 parts by weight
50 parts by weight of polyester resin (manufactured by Toyobo Co., Ltd .: trade name “Pylon 20SS”)
Thickness: 0.5 μm (dry film thickness)
[0147]
[3] Adhesive layer
Constituent material: Acrylic adhesive (Product name: “PL Thin” manufactured by Lintec Corporation)
Thickness: 30 μm (dry film thickness)
[0148]
[4] Release sheet base material
Constituent material: Dust-free paper (Made by Lintec: Product name “Clean Paper”)
Thickness: 70 μm
[0149]
[5] Release agent layer
Constituent material: Olefin-based thermoplastic elastomer containing ethylene propylene copolymer (Mitsui Chemicals, Inc .: trade name “Toughmer P-0280G”, density 0.87 g / cm^Three50 parts by weight
Polyethylene resin (manufactured by Sumitomo Chemical Co., Ltd., linear low density polyethylene: trade name “HI-αCW2004” density 0.908 g / cm^Three50 parts by weight
(This polyethylene is synthesized with Ziegler-Natta catalyst)
Thickness: 15 μm
[0150]
[6] Adhesion enhancing layer
Constituent material: Polyethylene (manufactured by Sumitomo Chemical Co., Ltd. Low density polyethylene: Trade name “L-405H” density 0.924 g / cm^Three)
Thickness: 15 μm
[0151]
(Example 2)
An adhesive body was produced in the same manner as in Example 1, except that the constituent material of the antistatic layer was a π-electron conjugated conductive polymer (manufactured by Nippon Carlit Co., Ltd .: trade name “PAS-B”). The thickness was 0.5 μm (dry film thickness).
[0152]
(Example 3)
The antistatic layer is composed of 100 parts by weight of a tin oxide conductive filler (Ishihara Sangyo Co., Ltd .: trade name “SN-100P”) and a π-electron conjugated conductive polymer (Nippon Carlit Co., Ltd .: trade name “PAS-B”. ]) Except having set it as 50 weight part, it carried out similarly to Example 1, and manufactured the sticking body. The thickness was 0.5 μm (dry film thickness).
[0153]
Example 4
As an antistatic layer, an adhesive body was produced in the same manner as in Example 1 except that a thin film of Pd was formed by sputtering. The thickness was 0.01 μm.
[0154]
(Example 5)
An adhesive body was produced in the same manner as in Example 1 except that the thickness of the pressure-sensitive adhesive layer (dry film thickness) was 10 μm.
[0155]
(Example 6)
By extrusion lamination, an adhesion enhancing layer was formed on one side of the release sheet substrate, and a release agent layer was further formed on the surface of the adhesion enhancing layer to produce a release sheet.
[0156]
Antistatic layers were formed on both sides of the substrate by a knife coating method. Furthermore, a pressure-sensitive adhesive layer was formed on the surface of each antistatic layer by a knife coating method to prepare a pressure-sensitive adhesive sheet.
[0157]
A release sheet was bonded to both sides of the pressure-sensitive adhesive sheet prepared in this manner to prepare an adhesive body.
The configuration of each layer is as follows.
[0158]
[1] Base material
Constituent material: Polyethylene terephthalate
Thickness: 38 μm
[0159]
[2] Antistatic layer
Constituent material: Tin oxide conductive filler (Ishihara Sangyo Co., Ltd .: trade name “SN-100P”) 100 parts by weight
50 parts by weight of polyester resin (manufactured by Toyobo Co., Ltd .: trade name “Pylon 20SS”)
Thickness: 0.5 μm (dry film thickness)
[0160]
[3] Adhesive layer
Constituent material: Acrylic adhesive (Product name: “PL Thin” manufactured by Lintec Corporation)
Thickness: 30 μm (dry film thickness)
[0161]
[4] Release sheet base material
Constituent material: Dust-free paper (Made by Lintec: Product name “Clean Paper”)
Thickness: 70 μm
[0162]
[5] Release agent layer
Constituent material: Olefin-based thermoplastic elastomer containing ethylene propylene copolymer (Mitsui Chemicals, Inc .: trade name “Toughmer P-0280G”, density 0.87 g / cm^Three50 parts by weight
Polyethylene resin (manufactured by Sumitomo Chemical Co., Ltd., linear low density polyethylene: trade name “HI-αCW2004” density 0.908 g / cm^Three50 parts by weight
(This polyethylene is synthesized with Ziegler-Natta catalyst)
Thickness: 15 μm
[0163]
[6] Adhesion enhancing layer
Constituent material: Polyethylene (manufactured by Sumitomo Chemical Co., Ltd. Low density polyethylene: Trade name “L-405H” density 0.924 g / cm^Three)
Thickness: 15 μm
[0164]
(Comparative Example 1)
The constituent material of the antistatic layer is an ionic antistatic agent (Mitsubishi Chemical Co., Ltd .: trade name “Saftmer ST-2000H”, thickness: 1 μm), and the release agent layer is made of a silicone release agent (Toray Silicone Co., Ltd.) Manufactured: A bonded body was manufactured in the same manner as in Example 1 except that the product name was “SRX-357” and the thickness was 1 μm (dry film thickness).
[0165]
(Comparative Example 2)
An adhesive body was produced in the same manner as in Example 1 except that the antistatic layer was not formed.
[0166]
2. Evaluation
About the sticking body produced by said each Example and comparative example, peeling voltage, surface resistivity, the amount of ions, and the amount of silicone compounds were measured. The measuring method is as follows.
[0167]
(1) Stripping voltage
It was left in an environment with an average temperature of about 23 ° C. and an average humidity of 65% RH for 30 days after the production of the sticking body. After leaving, first, the sticking body was cut into a 10 × 10 cm square. Next, the adhesive sheet was peeled from the release sheet at 500 mm / min. At this time, the charging potential charged on the pressure-sensitive adhesive sheet was measured from a distance of 50 mm using a current collecting potential measuring device (trade name “KSD-6110” manufactured by Kasuga Denki Co., Ltd.) in an environment of 23 ° C. and humidity 65% RH. (Measurement lower limit 0.1 kV).
[0168]
(2) Surface resistivity
It was left in an environment with an average temperature of about 23 ° C. and an average humidity of 65% RH for 30 days after the production of the sticking body. After leaving, first, the sticking body was cut into a 10 × 10 cm square. Next, the adhesive sheet was peeled from the release sheet.
[0169]
Thereafter, in accordance with JIS K 6911, the surface resistivity was measured with respect to the substrate surface, antistatic layer surface and pressure-sensitive adhesive layer surface using a surface resistivity measuring machine (trade name “R-12704” manufactured by Advantest Corporation). did. The surface of the antistatic layer was measured before forming the pressure-sensitive adhesive layer.
[0170]
(3) Ion content
For 30 days after preparation of the sticking body, the sticking body was left in an environment having an average temperature of about 23 ° C. and an average humidity of about 65% RH. After leaving, first, the sticking body was cut into a 3 × 3 cm square. Next, the adhesive sheet was peeled from the release sheet. Next, extraction operation was performed for 30 minutes with respect to an adhesive sheet using 20 degreeC pure water of 80 degreeC. Next, for this water, using an ion chromatograph analyzer (manufactured by Yokogawa Electric Corporation: trade name “IC500”), NO_x ^-, Cl^-, PO_Four ^3-, F^-, SO_Four ^2-, K⁺, Na⁺, Ca²⁺Each concentration of was analyzed and measured. Then, from the measurement results obtained, the amount of these ions contained per unit area in the pressure-sensitive adhesive sheet was determined (measurement lower limit value 5 μg / m²).
[0171]
(4) Silicone compound amount
For 30 days after preparation of the sticking body, the sticking body was left in an environment having an average temperature of about 23 ° C. and an average humidity of about 65% RH. After leaving, first, the sticking body was cut into a 10 × 10 cm square. Next, the adhesive sheet was peeled from the release sheet. Next, extraction operation was performed for 30 seconds with respect to the adhesive sheet using 23 degreeC and 10 ml of n-hexane. Next, the extracted n-hexane was dried on an agate mortar. Next, a tablet is prepared from the obtained dried product and 0.05 g of potassium bromide, and the content of the silicone compound in the tablet is determined using a beam condenser type FT-IR (manufactured by PerkinElmer: trade name “PARAGON1000”). ). Then, from the obtained measurement result, the amount of the silicone compound contained in the pressure-sensitive adhesive sheet per unit area was determined (measurement lower limit value 50 μg / m²).
These results are shown in Table 1.
[0172]
[Table 1]

[0173]
As apparent from Table 1, in Examples 1 to 6, the surface resistivity of the antistatic layer surface was 10⁶-10⁸Regardless of the surface resistivity of the surface of the pressure-sensitive adhesive layer, Ω and a value within an appropriate range, the stripping voltage was all below the detection limit, and an excellent antistatic effect was recognized. Moreover, the amount of ions and the amount of silicone compound were below the lower limit of detection.
[0174]
On the other hand, in Comparative Example 1, the surface resistivity of the surface of the antistatic layer is 10⁸The value of Ω and the proper range, the stripping voltage was below the lower detection limit, but the ion content was 1.4 mg / m²The amount of silicone compound is 5000 μg / m²Met.
[0175]
In Comparative Example 2, the amount of ions and the amount of silicone compound were not more than the detection lower limit value, but the stripping voltage was 5.0 kV. Moreover, when peeling a release sheet from an adhesive sheet, the adhesive sheet was wound around the tip of the tweezers, and the operability was also inferior.
[0176]
【The invention's effect】
As described above, according to the present invention, it is possible to obtain a pressure-sensitive adhesive sheet and a sticking body which can prevent the occurrence of peeling charge and substantially contain no ions.
[0177]
Therefore, the use of the pressure-sensitive adhesive sheet or sticking body of the present invention can prevent a decrease in operability when the pressure-sensitive adhesive sheet is peeled, and the performance of a hard disk drive device or the like caused by the presence of static electricity or ions. Deterioration, breakage, etc. can be prevented.
[0178]
Further, by making the adhesive sheet and the sticking body substantially free of the silicone compound, the hard disk drive device is less prone to trouble, and the reliability as the device is further improved.
[0179]
In particular, when an olefin-based thermoplastic elastomer and a polyethylene resin are used as the release agent, the release property is more excellent, and the release sheet can be easily and reliably peeled off.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing a first embodiment of an adhesive body of the present invention.
FIG. 2 is a cross-sectional view showing a second embodiment of the bonded body of the present invention.
[Explanation of symbols]
1a, 1b Adhering body
2a, 2b adhesive sheet
21 Base material
22 Antistatic layer
221, 222 Antistatic layer
23 Adhesive layer
231,232 Adhesive layer
3 Release sheet
31 Release sheet base material
32 Release agent layer

Claims (7)

A pressure-sensitive adhesive sheet used in a manufacturing process or an assembling process of a hard disk drive device or its parts,
A base material, a pressure-sensitive adhesive layer composed of a pressure-sensitive adhesive, and a nonionic antistatic layer interposed therebetween,
The pressure-sensitive adhesive sheet is characterized in that the antistatic layer contains polyaniline , which is a π-electron conjugated conductive polymer, as an antistatic agent. The pressure-sensitive adhesive sheet according to claim 1, wherein the antistatic layer has a surface resistivity of 1 × 10 ⁴ to 1 × 10 ¹² Ω.   The pressure-sensitive adhesive sheet according to claim 1 or 2, wherein the pressure-sensitive adhesive sheet contains substantially no silicone compound.   The pressure-sensitive adhesive sheet according to any one of claims 1 to 3, wherein the antistatic layer and the pressure-sensitive adhesive layer are provided on both sides of the base material, respectively.   The sticking body characterized by laminating a release sheet on the pressure-sensitive adhesive layer of the pressure-sensitive adhesive sheet according to any one of claims 1 to 4.   The sticking body according to claim 5, wherein the release sheet does not substantially contain a silicone compound.   The sticking body according to claim 5 or 6, wherein the release sheet has a release agent layer containing an olefin-based thermoplastic elastomer and a polyethylene resin.

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